La synthbse de la 5-et de la 7-trifluorom6thyl-quinol6ine (11 et 111) a partir de la m-trifluorotoluidine (I) ayant deja 6t6 r6alis8e1), nous exposons ici celle de la 6-et de la 8-trifluorom6thyl-quinoleine (IV et V). Celle-ci est beaucoup plus laborieuse en raison de la difficult6 de la preparation des produits de depart, 1'0-et la p-trifluorot oluidine .Rouche2) avait deja prepare 1'0-et le p-nitro-trifluorotolubne, en nitrant le m-ac6tamino-trifluorotolubne, et en d6saminant ensuite les produits de nitration. Au eours du m6me travail il a obtenu 1'0 -trif luorot oluidine.Cette m6thode &ant assez longue et le rendenient mddiocre, nous avons essay6 d'autres m6thodes dans l'espoir d'arriver plus facilement aux produits diisirds.La nitration du trifluorotol~bne~) donne presque exclusivement le dbriv6 mbta, c'est pourquoi nous avons essay6 de preparer le trichloro-p-nitrotolubne en chlorurant le p-nitrotolubne; sa fluoruration aurait dii nous donner directement 1s trifluoro-p-nitrotolubne.Nous n'avons pas reussi h introduire les trois atomes de ehlore dans le groupement m6thyle. Jusqu'h 145O, il n'y a substitution que d'un atome d'hydrogbne. Si on augmente la tempi.rature, on constate la formation, dans la phase gazeuse, d'un peu de dichloro-p-nitrotolubne. Si on diipasse M O O , l'absorption de chlore devient plus rapide, mais en meme temps on constate la formation d'eau, et dans le produit final de la reaction, on trouve un melange des chlorures de l'acide p-chlorobenzoique et de l'acide p-nitrobenzofque. Suivant les conditions de l'opiiration, la quantit6 de chlorure de l'acide p-chlorobenzo'ique peut atteindre 40 yo de la masse totale du produit de la r6action.La substitution du groupe nitro par le chlore, lors d'une chloruration, n'a pas encore 6tB signalee. Cette curieuse riiaction se produit probablement suivant le schema VI-X.A noter que les melanges de diverses proportions des acides p-chlorobenzoiques fondent a des temperatures comprises entre les temperatures de fusion de ces acides4).
Some insight into the constitution of carpaine, the alkaloid in the leaves of Cnrica p a p n y n L. was obtained by one of us1) long ago. We have recently been able to confirm and extend these earlier observations, chiefly by demosstrating the presence of a pyrrolidine ring, and by definitely identifying suberic and azelaic acids as oxidation products. The former was previously surmised, but not proved, to be a, 8-dimethyladipic acid. We have further found that carpamic acid C,,H,,O,N is formed from carpaine C,,H2,02N not only by the action of acids, as previously described, but also readily by that of alkali in alcoholic solution, thus supplying further evidence of A lactone structure. Since it appears t o be impossible t o regenerate the lactone from the hydroxy acid, carpaine is probably not a y -or a 8-lactone. The pyrrolidine nucleus is shown by dehydration with selenium, when four hydrogen atoms are lost and a pyrrole derivative is formed, for which the name cccrpyrine is suggested; on subsequent catalytic hydrogenation these four hydrogen atoms are again taken up and a base results, closely resembling the original alkaloid, and doubtless differing from it only in the stereochemical arrangement of one carbon atom.The place of attachment of the long carbon chain to the pyrroMine ring has not been proved conclusively but the a-position appears to be very probable. A priori it is tempting to assume some relationship to a naturally occurring fatty acid and to place all the carbon atoms of the molecule in an unbranched chain, which would make carpaine an a-pyrrolidine derivative, like nicotine, hypine and cocaine (compare Willstztter's phytosynthetical speculations2). The constitution might then be that of formula I, which we put forward merely as a basis of discussion.
The alkaloid (−)‐laurepukine is shown to possess one of the epimeric N‐oxide structures 4 or 5. Oxidation of (−)‐pukateine (3) by hydrogen peroxide gives (−)‐laurepukine and, as a second product, 6‐epi‐laurepukine.
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